Papillon Helicopters Aerospatiale AS350D accident
Aerospatiale AS350D · Accident: total loss of engine power (mechanical failure) en route
From Waikoloa, HI to an unrecorded destination
Event
- NTSB case
- LAX89LA281
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Charter & commuter
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aerospatiale AS350D
- Aircraft type
- Aerospatiale AS350
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N35970
- Operator
- Papillon Helicopters
- Onboard fatalities
- Unknown
- Route
- From Waikoloa, HITo not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 135: Air Taxi & Commuter
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · descent
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Total loss of engine power (mechanical failure)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Company maintenance personnel › Maintenance, 100-hour inspection, poor
- Fluid, oil › Starvation
- Lubricating system, oil seal › Worn
- Pilot in command › Aircraft preflight, inadequate
- Turboshaft engine, gas generator turbine shaft › Failure, total
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE VFR SIGHT-SEEING FLIGHT WAS BEING CONDUCTED UNER 14 CFR 135. WHILE DESCENDING INTO A MOUNTAINOUS AREA THE PILOT FELT A SEVERE VIBRATION ABT 10 - 15 SECONDS BEFORE THE ENGINE FAILED. THE PLT EXECUTED AN AUTOROTATION IN THE UPWARD SLOPING TERRAIN AND THE HELICOPTER ROLLED-OVER ON TOUCHDOWN. THE ENGINE EXAM DSCLSD THAT THE POWER TURBINE SHAFT AND THE NOS. 2 & 3 BEARINGS FAILED DUE TO OIL STARVATION AND DISPLAYED EXTREME HIGH TEMPERATURE DISTRESS. THE CHIP DETECTOR O-RING SEAL WAS EXCESSIVELY WORN. OIL RESIDUE STREAKING WAS FOUND ON THE OUTSIDE OF THE FUSELAGE/ TAILCONE ASSY AND THE VERTICAL/HORIZONTAL STABILIZERS.
Probable cause
A CATASTROPHIC FAILURE OF THE POWER TURBINE SHAFT AND BEARINGS. THE FAILURE WAS A RESULT OF OIL STARVATION DUE TO AN EXCESSIVELY WORN CHIP DETECTOR O-RING SEAL,INADEQUATE MAINTENANCE AND PREFLIGHT. CONTRIBUTING FACTOR(S) WAS: THE MOUNTAINOUS TERRAIN.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX89LA281
- Event ID
- 20001213X29162
- Case number
- LAX89LA281
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 65d68375f1dee8878a3f0181915390f86b7b13c19d25bc7e6a21468522e36b01; retrieved 2026-09-18T19:09:05.900Z.